High-performance filters from biomimetic wet-adhesive nanoarchitectured networks

Abstract

Two-dimensional (2D) networks assembled by nanoscale fibers are attractive for the design of equipment for personal and environmental protection, but are limited by insufficient structural and performance control. We report a facile route, based on blend electrospinning/netting technology, for the preparation of a hybrid biologically inspired nanofiber network (nanofiber-net) filter with nanoscale fiber diameters (∼27 nm), a 2D stable spider-web-like structure, and mussel-mimetic wet-adhesive surfaces. Manipulating the formation and phase separation of the charged droplets ejected from a Taylor cone by controlling the mussel-mimetic adhesive molecules, enabled the generation of biomimetic nanofiber-nets on a large scale. The resulting filters show the remarkable nanostructural properties of small pore size (∼0.28 μm), high specific area, enhanced surface adhesion and wettability, high-performance applications in air filtration (>99.99% PM_0.3 efficiency under >90% humidity, ∼0.13% of atmosphere pressure) and water purification (>99.9% efficiency, 453 L m⁻² h⁻¹ gravity-driven flux). This work offers an innovative design of high-performance nanofiber filters for a broad range of applications.